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    <title>Document</title>
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  <body>
    <script>
      //请实现以下效果
      function add(a, b, c) {
        return a + b + c
      }
      // console.log(add.length);

      const res = add(1, 2, 3) //6

      //要求声明一个curry函数，函数add经过curry函数的处理后，每次调用只能接收一个参数
      const curry = (fn) => {
        let a = function (...args1) {
          if (args1.length >= fn.length) {
            return fn.apply(this, args1)
          } else {
            return (...args2) => {
              return a.apply(null, [...args1, ...args2])
            }
          }
        }
        return a
      }

      // const curry = (fn) => {
      //   let i = 1
      //   let a = function (...args) {
      //     if (args.length !== i) {
      //       throw new Error('只能输入一个参数')
      //     }
      //     i++
      //     if (fn.length === args.length) {
      //       return fn(...args)
      //     } else {
      //       return a.bind(null, ...args)
      //     }
      //   }
      //   return a
      // }

      let addCurry = curry(add)

      // console.log(addCurry);
      const res2 = addCurry(1)(2)(3) //6

      console.log(res2)
    </script>
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